Turbine driven pump



1 t e e h S S t e e h s 2 H. E. MEANS TURBINE DRIVEN PUMP June 17, 1958 Filed oct. 14, 1953 1 Ing lll/11111011110;

June 17, 1958 E, MEANS TURBINE DRIVEN PUMP Filed 000. 14. 1953 %\N,\. QNMSGQQQQ /NVENTOR HERBERT E. MEANS TURBINE DRIVEN PUMP United States Patent i Herbert E. Means, Hartford, Conn., assignor, by mesne assignments, to the United States of America as represented by the United States Atomic Energy Commission This invention relates to a turbine driven pump, and refers more particularly -to a spool-type pump having two stages of pumping anda two-stage turbine.

An object of this invention is to provide a means of pumping which comprises two turbine rotors rotating in the same direction with concentric shafts, each rotor driving a separate pump impeller.

Another object of this invention is to reduce the bearing speeds generally required in a pump of similar capacity.

A further object of this invention is to provide favorable inlet conditions to both impellers from a cavitation standpoint. Y

Another object of this invention is to provide a high pressure ratio pump which will pump water with reduced possibility of encountering cavitation near the boiling point, to a higher pressure.

A further object of this invention is to provide a spoolvtype pump in which the bearings are lubricated by the liuid being pumped. p

Another object of this invention is to provide a pump of smaller size and lighter weight than conventional pumps of like capacity.

Other objects yand advantages will be apparent from the specification, and lfrom the accompanying drawings which illustrate an embodiment of the invention.

. Fig. 1 is a vertical View in partial section of a pump showing a construction which is in accordance with the invention.

Fig. 2 is a dia-grammatical view showing the relation of said pump in a typicalsystem.

Referringl to the iigures, Fig. 1 shows the construction of the pump 2, comprising three main parts. The first part is the first-stage slow-speed pump impeller 4 4and its driving means which includes the second-stage low-speed turbine rotor disk 6 and blades 7. The second part is the second-stage high-speed pump impeller 8 and its driving means which includes the iirst-stage high-speed turbine rotor -disk 10 and blades 11. The third part is the housing y12 which encloses and mounts the pump impellers 4 and l8 and their respective driving means including the turbine rotor disks 6 and 10.

The housing 12 in the construction shown in Fig. 1 is made up of iive parts. However, it is to be understood that the housing may be constructed in any other number of ways according to ythe size and shape of pump desired. These live parts include a turbine inlet housing member 14, stator holding ring 16, turbine outlet and pump inlet housing member 18, pump intermediate housing member` 20 and pump end plate housing member 22.

The turbine inlet housing member 14 comprises an annular member 15 having an annular passageway 24 at one end thereof. `A conduit 26 is connected to said annular passageway 24 for directing steam thereinto. In Fig. 2 a turbine control valve 202 is shown located in conduit 26. A flange 28 is attached to the free end of said conduit 26 flor connecting it to a steam supply. An outwardly'extending flange 38 is located at the other end of said annuice 2 i. lar member 1`5`for` iixing sai-d turbine inlet-housing member 14 to the statorholding ring 16 and turbine outlet pump inlet housing 18.v A plurality of recesses 32 are equally spaced, each at the same radius from the pump axis, around the inner side of the annular member '14 in a thickened portion 33 adjacent passageway 24. A short passageway 34 connects eachof these recesses to the annular passageway 24. A plate 25 is connected to the inner side of the casing surrounding the passageway 24. These recesses 32 are adapted to receive nozzle members 36 which may be fixed therein by any means desired. As can be seen, various size nozzles can be used to control the steam passing therethrough. It is also to be noted that while the recesses are shown having their axes parallel to the pump axis, these recesses may be made lhaving their axes at an angle to sai-d pump axis to control the direction of steam passing through the nozzle members set in said recesses. A turbine blade casing 35 is located between said recesses and said flange 30.

Stator holding ring 16 comprises an annular member having an outer holding iiange 38 which is adapted to engage and be iixedly attached to ange 30 of ksaid turbine inlet housing member 14 and a ixed vane portion 4i?. This iixed vane portion 40 `consists of an outer circular member 42 connected to said flange 38, an inner circular member 44, and a plurality of vanes 46. fixed between the inner surface 41 ofmem'ber 42 and the outer surface 43 of member 44. Inner surface 41 forms .a continua-tion of the inner surface of turbine blade casing 35. While these vanes are shown fixed, they may be mounted for adjustment by manual or automatic means. A ange 48 extends from the inner side of member44 yfor a purpose to be hereinafter described. p v

Turbine outlet and pump inlet housing member 1S comprises Ia main center annular 'bearing supporting member 50 having an outwardly extending flange 52 at one end which is adapted to engage and 'be iixedly attached to ange 38 of said stator holding ring 16 and an outwardly extending flange 54 located at its other end for fixing said turbine outlet and pump inlet housing member 18 to the pump intermediate housing member Ztl. Flange 52 is connected to center member 50 by a turbine outlet collector 56 and a turbine blade casing 57. T-he inner surface of `turbine blade casing 57 forms a continuation of inner surface 41. A conduit 58 is connected to said collector to direct the steam away from said collector. Flange 60 is attached lto the free end of said conduit for connecting said conduit to an ex'haust. Flange 5d is connected to center member l50 by a water inlet scroll section 62, casing plate section 64 and a first-stage collector ring 66. The casing plate 64 is contoured to fit the curved edges 68 of the blades 70 of the first-stage pump impeller 4. A conduit 51 is connected to said scroll section to direct the water thereto.

When turbine inlet housing member 14, stator holding ring 16 and turbine outlet and pump inlet housing member` 18 are assembled with their iianges, 30, 3-8 and 52 respectively, held ixedly together lby bolts 104, a space exists between lthe exit ends of nozzle members 36 and thek inlet ends of vanes 46 to receive blades 11 and a space exists between the exit ends of vanes 46 and the inlet of' turbine outlet collector 56 to receive blades 7. `These blades are mounted in a mannerto be hereinafter described.

The pump intermediate housing member 20 compri-ses an :annular member 72 having an outwardly extending liange 74 at one end which is adapted to engage and be iixedly attached to iiange 54 of said`turbine outlet and pump inlet housingmem'ber 18 and an outwardly ex-l tending iiange 76 located at its other end for fixing said pump intermediate housingV mem'ber .2(l to the pump end plate housing member 22. This annular member 72 has Patentedk June 17, 19,58l

a ycentral bearing supporting member 78 fixed therein. v

This bearing member 78 is attached to member 72 by a backing plate 80 for the back of first-stage pump impeller 4 and interstage guide vanes 82. Annular member 72 has a casing plate section 84 which is contoured `to fit the curved edges 86 of the blades 88 of the secondst-age pump impeller 8. The portion of member 72 between the casing plate 84, and flange 86 is formed having a cross section which is substantially semi-circular as at 90.

The pump end plate housing member 22 consists of a plate having a iiange 92 at its outer periphery which is adapted to engage and be lixedly attached to fiange 76 of said pump intermediate housing member 20. A portion 94 of said plate serves as a backing plate for the back of second-stage impeller 8 and a portion of said plate located between said backing plate portion and fiange 92 has a cross section which is substantially semicircular as at 96'. A conduit 98 is connected to the second-stage collector ring formed by the semi-circular portions 90 and 96 for directing the pumped fluid therefrom. A flange 102 is located on the free end of conduit 98, for connecting it to a pump discharge line.

The first part of the pump 2 which has been referred to as the first-stage slow-speed pump impeller .4 and its driving means which includes the second-stage low speed turbine rotor disk 6 and blade 7 is positioned in said housing in the following manner. The rotor disk `6 has a driving shaft 104 aliixed thereto which is supported in the main center annular bearing supporting member t) of turbine outlet and pump inlet housing member 18 by outer bearings 112 and 114. Bearings 112 and 114 are fixed in said annular bearing supporting member. Bearing 114 is ftanged out at 116 to provide a thrust ybearing at this 'point with the rotor hub 118 of disk 6. These bearings 112 and 114 are of the water lubricated type well known in the art of bearings.

The shaft 104 has a bore 106 therethrough which is positioned co-axially with said shaft. The free `end of said shaft has splines 116 located around its outer surface adjacent the end and is threaded at the end with threads 110. The pump impeller 4 has a hole located therethrough which is internally splined with splines 122. The pump impeller 4 is positioned on driving shaft 104 with its internal splines 122 mating with the external splines 116 of said shaft. Washer 126 is placed over the threaded end of shaft 104 which protrudes through the hole in said pump impeller 4 and a nut 128 is threadably secured to the threads 110. This action presses the end of impeller 4 against abutment 117 formed at the end of splines 116. In this position the blades 7 of the rotor disk 6 are positioned in the turbine blade casing 57 with the outer surface 130 of the blade roots 132 forming an extending surface from outer surface 43 of member 44. Blades 7 may be fixed to said rotor disk 6 by any means desired.

The second part of the pump 2 which has been referred to as the second-stage high-speed pump impeller 8 and its driving means which includes the first-stage highspeed turbine rotor disk and blades 11 is positioned in said housing in the following manner. The rotor disk 10 has a driving shaft 136 aiiixed thereto which is supported in the bore 106' of shaft 104 by inner bearings 138 and 140. Bearings 138 and 140 are fixed in bore 106. Bearing 140 is fianged out at 142 to provide a thrust bearing at this point with the rotor hub 144 of disk 10. These bearings 13S and 140 are also of the water lubricated type.

The free end of shaft 136 has splines 146 located around its outer surface adjacent to the end and is threaded at the end. The pump impeller 8 has a splined hole located therethrough. The pump impeller 8 is positioned on driving shaft 136 with its internal splines matv ing with the external splines 146 of said shaft. Washer 148 is placed over the threaded yend of shaft 136 which protrudes through the hole in said pump impeller 8, and a nut 150 is threadably secured to the threaded end of said shaft. This action presses the end of impeller 4 against abutments 152 formed at the end of splines 146. In this position the blades 11 of the rotor disk 10 are positioned in the turbine blade casing 35 with the outer surface 154 of the blade roots 156 forming an extending surface from the outer edges of recesses 32 to the outer surface 43 of member 44.

An inner 'stage turbine seal of the labyrinth type is formed between a raised portion 170 on rotor hub 144 and the inner periphery of annular plate 172 which is fixed to a liange 48 on stator holding ring 16 by a holding ring 174 and bolts 176. This seal is also aided by the sealing action obtained between the edges of the outer surface 43 of member 44 and the engaging edge of outer surface 130 of blade 7 and the edge of the outer surface 154 of blade 11.

Water is directed to bearings 112 and 114 at a sufficient pressure through conduit 160, passageway 162 of turbine outlet and pump inlet housing member 18 and annulus 164 formed between the main center bearing supporting member 50 and the outer surface of shaft 104. Bearings 138 and 140 are lubricated by water from annulus 164 which is directed to annulus 166 formed between the inner surface of shaft 104 and the outer surface of shaft 136 by holes 168. The water required for lubrication of bearings may be supplied from either the first-stage collector ring 66' or the second-stage collector ring. This determination, however, will depend upon the pressure of the steam in turbine outlet collector 56. In Fig. 2 conduit 160 is shown connected to conduit 98 and having a water control valve 200.

In the system shown in Fig. 2 the pump delivers water at a very high pressure from high speed impeller 8 through conduit 98 to a boiler 204. This water is also delivered back to the pump 2 through conduit 212, water control valve 200 and conduit for use in lubricating the bearing means therein. Boiler 204- delivers steam at a very high pressure, first, to a turbo generator 206 and second, to the high speed turbine rotor 10 of pump 2 through conduit 208, turbine control valve 202 and conduit 26. Steam at a lower pressure leaves turbo generator 206 and enters condenser 210. Steam at a lower pressure also leaves low speed turbine rotor 6 through conduit 58 and enters condenser 210. Condenser 210 delivers sub-cooled water near its boiling point through conduit 51 to low speed impeller 4.

Although a specific pump and system has been shown and described herein for the purpose of illustration, it will be evident to those skilled in the art that this invention is capable of various modifications and adaptations within the scope of the appended claims.

I claim:

1. A turbine driven liquid pump including a housing, a first shaft, first bearing means in said housing comprising axially spaced aligned bearing members having a bore therethrough of smaller diameter than the inside diameter of said housing, said irst shaft being mounted for rotation in said first bearing means and forming with said housing an annular chamber between said bearing members, a passage through said housing into said chamber, a first turbine rotor having turbine blades fixed to one end of said shaft, a first liquid pump impeller fixed to the other end of said shaft, said housing forming a first liquid pump casing around said first liquid pump impeller having an inlet and outlet, said housing forming a first turbine casing around said first turbine rotor, said first shaft having a bore therethrough, second bearing means in said bore comprising axially spaced aligned bearing elements, a second shaft mounted for rotation in said second bearing means and spaced from said first shaft by said second bearing means to form a second annular chamber between said bearing elements, a second turbine rotor having turbine blades fixed to one end of said second shaft, a second liquid pump impeller fixed to the other end of said second shaft, said housing forming a second liquid pump casing around said second liquid pump impeller having an inlet and outlet, said housing forming a second turbine casing around said second turbine rotor, the outlet of one liquid pump casing being connected to the inlet of the other liquid pump casing, means for lubricating said first and second bearing means, said last named means including a conduit connected to the outlet of a liquid pump casing for supplyingy the pumped liuid from said outlet through said passage into said first chamber, and means for supplying s'aid pumped fiuid to s'aid bearing elements comprising passage means through said first shaft between said bearing members for connecting said second chamber with said first chamber.

2, A turbine driven liquid pump having in combination, a housing having a bearing supporting member, a bearing located at each end of saidmember, a first shaft being supported for rotation in said bearings, said first shaft forming with said bearing supporting member between said bearings a first annular space, a first turbine rotor having blades fixed to one end of said first shaft, a first liquid pump impeller fixed to the other end of said first shaft, said housing forming a first turbine casing around said first turbine rotor, said housing forming a first liquid pump casing around said first liquid pump impeller, said first shaft 'having a bore therethrough, a bearing located at each end of said bore, a second shaft supported for rotation in said bearings, said second shaft forming with said bore between said .bearings a second annular space, a second turbine rotor having blades xed to one end of said second shaft, a second liquid pump impeller fixed to the other end of said second shaft, said housing forming a second turbine casing around said second turbine rotor, said housing forming a second liquid pump casing around said second liquid pump impeller, said first shaft having a hole therein connecting said first annular spa-ce with said second annular space,y said bearing supporting member having a hole therethrough oonnected at its inner end to the first annular space, a conduit connected to the outlet of a liquid pump casing at one end and to said hole in said bearing supporting member at its vouter end.

3. A turbine driven liquid pump having in combination, a housing having a, bearing supporting member, a bearing located at each end of said member, a first shaft being supported for rotation in said bearings, said first shaft forming with said bearing supporting member between said bearings a first annular space, a first turbine rotor having blades fixed to one end of said first shaft, a first liquid pump impeller fixed to the other end of said first shaft, said housing forming a first turbine casing around said first turbine rotor, said hou-sing forming a first liquid pump casing around said first liquid pump impeller, said first shaft having a bore therethrough, a bearing located at each end of said bore, a second shaft being supported for rotation in said bearings, said second shaft forming with said bore between said bearings a second annular space, a second turbine rotor having blades fixed to one of said second shaft, a second liquid pump impeller fixed to the other end of said second shaft, said housing forming a second turbine casing around said second turbine rotor, said housing forming a second liquid pump casing around said second liquid pump impeller, said first shaft having a hole therein connecting said first annular space with said second annular space, said bearing supporting member having a hole therethrough connected at its inner end to the first annular space, a conduit connected to the outlet of a liquid pump casing at one end and having its other end connected to said hole in said bearing supporting member at the outer end of the latter, a control va'lve 1ocated in said conduit for controlling a fluid passing from said outlet of said liquid pump casing through both said first and second annular spaces to said bearings.

References Cited in the file of this patent UNITED STATES PATENTS 1,197,155 Sebald Sept, 5, 1916 1,238,731 Anderson Sept. 4, 1917 2,451,944 Hall Oct. 19, 1948 2,528,635 Bell et al. Nov. 7, 1950 2,611,532 Ljungstrom Sept. 23, 1952 2,625,790 Petrie Ian. 20, 1953 FOREIGN PATENTS 519,539 Belgium May 15, 1953 

